Aluminium salt of hydroxy carboxylic acids



Fatenied Aug. 24,1943

i ruise stares; e swam, a thermos-a;

I I Jsph Ni'eflefcmfis Riverside; and William 0i Q Dawson, Greenwich, Conn., assignors to Am I 1. c n. G an d corporation of 'Maine i f f Nan -swing: Applicationjanua-ry351L195;

green-a1 No. 376,8 2. r 1

. wa to -sezi a isy anv'ntionielates renew maples aluminurfi compounds of certain hyurexy arthen-1e acius-,-wn ties-as r ne'agentsror ai es and skins and as fi'liishin'iagents fbr- 'fihroih.tanned-' lathefi; The invention induces tn w compete -steed: selves, their methods of prepares treating compositions containing We have found that 100 basic co plexalu minuin compounds canbe prepared irony-certain aneleather:

hlydlOXY carboxylic acids by the-reacti'on'of in organic aluminum compoundslth'erewith in tne presence of, or with subsequent addition-of s'uita able "amountsof strong alkali'es; The oi'gani'' acids which have "found to form 100% basicof Whichare organic-carboxylic acids containing at least one hydroxy group in the alpha position with respect to -a carboxylic acid group.- The resulting products in addition to their utility as signifies a areas ease 'siieh asjsbdiuiii or 1 potassium and n equals a whol iiiiiiibeii', Iii "cases 1 and 3 above n p'ffib'ably equals unity and acid, 'luc'oniofacici ariuai' a -hyurb ii isobutyriii tog'sthrconst'it A do; are; three he; eenstit ute the t e em eiis nom argi ca e n pr ba mq ais fl n ih rs m und s P b gluconic acid, alpha-hydroxy ,isobutyric leather finishing agents alse possess wetting. 3

emulsifying and penetrating properties particularly in alkalinesolution, and are. further useful as mordantsi v I l The 100% basic complex aluminum salts of our invention are prepared by reacting aninorgenie g q o npound sucna an aluminum 3U tail ey-r'eieriiee to tnfollowin 'specific eiram salt, an alii'n'iinate or aluminum hydroxide with 1 j' iegg It. sn uid be understo dy hem-van that of, a strongalkalisuch assodium-or potassium hydroxide, Incarrying out the reaction it ises sential to three carboxylic acid groups presw ent for each aluminum moleculaiand therefore disselyed egual'quantitypf;water-by weight the amount to be employed-is based; first, on the wviththe. oiheat; Thesohitiongwasallowed number of 'moles of aluminum present and, secondly, on the degree of basicityof the'organic carboxylic acid; 'Ihus; for example, where one 7 mole of aluminum sulfate visused at least 6 moles 7 sodium aluri'iihate or aluminum hydroxide are used as the source of the aluminum, then the molar ratio of the carboxylic acid is of course half as much. vSuflicient alkali must be used to form the trisodium or;tripota'ssium' or other 100% basic trihydro'x'y tricarboxalato-aluniinate salts] of our invention as well as to neutralize any inorganic acid'groups thatkare introduced when an aluminum salt is used as aluminum.

the source of the 7 solution 1 precipitated; 2

, The comp1e i, 100% bmauamua salts of our invention are defined-by the probable structural formula" r e or. as parts o'tf a single"tiricarlooxi a e a ia ire a mo emi T sir s isr iizm ihaie iizilitifi three c 9M1 6; sw s needed ieel iinn swm: p nds m c mbin ti n wi h eieeralmar eaxiir enWe: ee e e ea b l.

acid radicals a. u|- l M acldradlcal,

in 'which case 'a mon omol ular compound isobhe latt tease, owever; it is sun possible it 1 theseei'zainples aregiileri primarily for purposesoi illustration andthat the invent-ionin its broad;

to cooliand then 2500 grams of Water in which,

4-1 era ssii m e bii fik e azer oxy i750- butyrieaeid had been prev'ously dis sqlyed with stirring and 'eaeiifigte a 6d perature rise;- The fir oduct obtairied was a clear solution of the'iconiplex,alumiriuh salt together i i with sodium sulfate. fIfl-ie bomfqieiialuminum salt solution'formd can be evaporated to dryness under? a vacuumbrrtthe salt is extremely 'hygrd' r scopiczrjUpon addition ofaoid' tethe,.a ueous.

it, oi tihejorg an-ic acid is;

. z ar aar i iin'o'l era moriofiaihoxyli acid mes-mixture was 7 I added a l the i iwiie ee ieiirit ii a a 'Finally a cold solution of 480'gran1s ('12 n oles) I of sodiumfhydroxide dissolvediri 1 920 7 2 j v i of slightheatins, The mixture w s stirred until a clear solution of the basic complex trisodiumtrihydroxyl' aluminum salt .of citric acid was formed. This salt has a higher solubility than; the complex salt of alpha-hydroxy isobutyric,

d not precipitate by thejadditio'n acid and woul of acid.

Example 3 v except that one-half of the sodium'hydroxide butyric acid to form the neutral salt lth'ereofi" To this neutral salt solution the aluminum sulfate was added and finally the remaining caustic solu- 7 tion. The same product was obtained as before in Example 1.

" Example 4 m The neutral sodium alpha-hydroxy isobutyrate was, formed byithe saponificati'on of 792.6 grams of ethyl alpha-hydroxy' isobutyrate with 240 grams of sodium hydroxide. The saponified product then usedl in the same'mannerlasf the sodium alpha-hydroxy isobutyrate, solution in ExampleB. The product was the same as in Exe ample; 1, ex cept forcthe presence ;of, ethyl alcohol in thesolution I a 7' 5 Example} 1 77.99 gramsKLmole) of 'aluminum hydroxide: and 120grams (3 moles) ofsodium hydroxide were addedto '300'grams' of water and the mixtureheated until a clear solution-resulted," The solutionrwasthencooled to'30"C. and a'solution' of-;'312.18 grams (3 moles) of alpha-hydroxy isobutyriofacid-dissolved in an equal weightof water was added to the solution of the mixed hyj -droxides'slowly and with constant agitation-j By this" method the trisodium trihydroxyl alphabutyro' aluminate solution"containedno extra-ff neous salt;

I E melef i 163.94 jgramS, ,(2 moles) i of sodium aluminate and lfillsgrams (l-smokes) ofQsod-ium hydroxide were added to zourgramsof water and the mixture heated and: stirred until a clear solution -re- :sulted. This mixture; wasthen; cooled to 30,lC.

and 504.2 grams' .(3 moles) ofatartaric acid diso solved in an equal weight-of water was addedj gradually; with agitation and cooled. 'This method also resulted in the formationof-kthe solution of thetrisodium-trihydroxyl aluminum salt of tar tarici-acid without the-presence of any extrane- 7 Having described'our new'chem-icalcompounds 7 and the manner infwhich the same areprepar'ed,

what we claim and desire to secure: by Letters; -Patentis:' r 1. A 100% basic complex aluminum-salt haying the following general formula:

where R; is selected from the group consisting of: 1),theacid radicals of three =molecules=ofa member ofthe group consisting of lactic, gluconic and alpha-hydroxyisobutyric acids, (2) thenormal acid radicals ofthree molecules of a mem ber of the group comprising tartaric and malic acids, 7 and. ,(3) the normal acid radical of vone molecule ofcitric acid,M is a memberof the group numin the form ofraluminum hydroxidlwith defined as (2). r r

2. A method of preparingthe 100% basic complex aluminum salts'of claim 1 which comprises 2] reacting in aqueous solution a water-soluble in- I organic aluminum compound'and a member of 2 "the group consisting of lactic, gluconic, alpha-hy- V droxy'isobutyric, tartaric; imalic and citric-acids The same solutions were used as Example 1' and theirtsodium and potassium salts'in the pres l r a i solution containing 6 moles and voyer was first I added to the solution of the alpha-hydroxyiso ence of 'suchan amount. of a member of the group 'consistin'gof isodium andpotassium hydroxides; 1 asis necessary to neutralize all acid present, the I proportions of aluminum compoundandacid' compound being such that there are-three car 1 'boxyl groups present for each aluminum-atom.; f

"A m od of re a in a Q;%; i mplex aluminum salt which comprises reactingin a que 1 oussolution one molar equ iyalentoi aluminumjin the fo f l m mima iate with hre'e mo j equivalents of alpha-hydroxy ,isobutyrio'il aoid the presence of six "molar: equivalents of a;n '1em+ ber ofthe group consisting of sodium and'p'otas; i I

slum hydroxides. 7

v 4. A methodof preparinga lOl)% basic com;

plex aluminum salt'which comprises reacting in aqueous solution one molar. equivalent :of .alumie Hthree molar equivalents. of .alpha-hydroxy-iso;

a 9 ia sin Qidi l nd pota m i 1 1 mm, 7

' butyric acid in th'prese'nceofB molar equivalents I I of a member of the group consistingfof sodium I and potasium hydroxides. 7 a

5, The compoundohaving' the formula? l C V p; I V v 6 3- mm av n the o mu a? 

